1. Field of the Invention
The present invention generally relates to a magnetic tape recording and/reproducing apparatus and, more particularly, to a cassette tape player of a type, though not exclusively limited thereto, which can accommodate either one of two different tape cassettes.
2. Description of the Prior Art
Cassette tape players are being manufactured compact in size and this is particularly true of ergonomic appliances. Cassette tape players of a type employing a cassette loading mechanism comprising a generally U-shaped cassette holder have long been well known in the art. Examples of the cassette loading mechanism hitherto employed are disclosed in, for example, the Japanese Laid-open Patent Publication No. 5-62311, published Mar. 12, 1993, (corresponding to U.S. patent application Ser. No. 07/936,592, filed Aug. 27, 1992, and EP Published Patent Application No. 530700-A2, published Mar. 10, 1993) and U.S. Pat. No. 5,172,284, issued Dec. 15, 1992.
However, with the advent of digitalization of acoustic systems, a relatively recent product in the field of cassette tape recording and/or reproducing apparatuses is a high-fidelity digital audio tape player. The digital audio tape player currently placed in the market is available in two types, namely, R-DAT (rotary head digital audio tape) recorders and S-DAT (stationary head digital audio tape) recorders, according to the different system protocols.
The R-DAT player makes use of a magnetic recording and/or reproducing head supported for rotation relative to a length of magnetic recording tape that is moved slantwise relative to the plane of rotation of the magnetic recording and/or reproducing head. In contrast thereto, the S-DAT player makes use of a magnetic recording and/or reproducing head supported stationary relative to a length of a magnetic recording tape that is moved relative to the magnetic recording and/or reproducing head. So far as a tape cassette is concerned, the both have no compatibility due to difference in sound recording format.
However, due to the use of the stationary head, the S-DAT player has a compatibility with the long-lasting, popular analog audio tape player in the sense that the S-DAT player can accommodate not only a digital compact cassette (DCC) designed specifically for use with the S-DAT player, but also an analog compact cassette (ACC) designed specifically for use with the analog audio tape player. The digital compact cassette and the analog compact cassette have many structural similarities with slight difference in dimension as will subsequently be discussed and, therefore, a cassette tape player having a capability of recording and/or reproducing not only a digital signal but also an analog signal is currently expected.
The currently suggested cassette tape player having the duel capability of recording and/or reproducing either one of the digital and analog signals can make use of either one of the analog compact cassette and the digital compact cassette, both being currently available in the market. The details of each of the analog compact cassette and the digital compact cassette will now be discussed with particular reference to FIGS. 9(a) to 9(c).
The analog compact cassette is shown by 5 in FIG. 9(a) in a front elevational view and comprises a generally rectangular box-like casing 5a having a width L1, a minimum thickness D1, a maximum thickness D2 greater than the minimum thickness D1 and a depth. The width L1 is defined as measured in a direction parallel to a reel-to-reel direction; both of the minimum and maximum thicknesses D1 and D2 are defined as measured in a direction parallel to an axis of rotation of the reels and conforming to the widthwise direction of a length of magnetic recording tape; and the depth is defined as measured in a direction perpendicular to the reel-to-reel direction and also to the axis of rotation of the reels.
The casing 5a referred to above includes rectangular top and bottom panels and a peripheral wall disposed between the top and bottom panels to keep them spaced apart a distance to define a tape chamber, all assembled together to render the tape cassette to represent a generally rectangular, generally flattened box-like configuration. The peripheral wall of the casing 5a includes front and rear wall sections, only the front wall section being shown by 5d in FIG. 9(a), and a pair of side wall sections. The front wall section 5d has at least first, second and third access windows 5e, 5f and 5g defined therein, said first access window 5e being adapted to receive a magnetic recording and/or reproducing head while said second and third access windows 5f and 5g are adapted to receive therein a pinch roller and a motor-coupled capstan.
The casing 5a accommodates therein a pair of freely rotatable reels 5c (FIG. 4) to which opposite ends of a length of magnetic recording tape are anchored, respectively, so as to extend from one reel to the other reel via an operative path substantially along the front wall section 5d by way of guide rollers rotatably disposed at respective corner areas adjacent the front wall section 5d.
The casing 5a of the analog compact cassette 5 has left-hand and right-hand guide bars 5h integral with the side wall sections so as to protrude laterally outwardly therefrom a distance indicated by L2 while extending in a direction conforming to the depth of the analog compact cassette 5.
As compared with the digital compact cassette which is indicated by 1 in FIGS. 9(b) and 9(c) and which will subsequently be described, the analog compact cassette 5 is unique in that respective front portions of the top and bottom panels of the casing 5d adjacent the first to third access windows 5e to 5g are raised upwardly and downwardly, as viewed in FIG. 9(a), thereby to define a bulged area 5b of the analog compact cassette 5. The maximum thickness D2 referred to above is represented by this front bulged area 5b.
On the other hand, the digital compact cassette shown by 1 in FIGS. 9(b) and 9(c) similarly comprises a generally rectangular box-like casing having a width L3, a thickness D3 and a depth. As is the case with the analog compact cassette 5 shown in FIG. 9(a), the width L3 is defined as measured in a direction parallel to the reel-to-reel direction, the thickness D3 is defined as measured in a direction parallel to the axis of rotation of the reels and conforming to the widthwise direction of a length of magnetic recording tape; and the depth is defined as measured in a direction perpendicular to the reel-to-reel direction and also to the axis of rotation of the reels.
Again similarly, the casing of the digital compact cassette 1 includes rectangular top and bottom panels and a peripheral wall disposed between the top and bottom panels to keep them spaced apart a distance to define a tape chamber, all assembled together to render the tape cassette to represent a generally rectangular, generally flattened box-like configuration. The peripheral wall of the casing of the digital compact cassette 1 includes front and rear wall sections and a pair of side wall sections. The front wall section has at least first, second and third access windows 1a, 1b and 1c defined therein, said first access window 1a being adapted to receive a magnetic recording and/or reproducing head while said second and third access windows 1b and 1c are adapted to receive therein a pinch roller and a motor-coupled capstan.
The casing of the digital compact cassette 1 has a pair of freely rotatable reels accommodated therein. Opposite ends of a length of magnetic recording tape are anchored the respective reels so as to permit the length of magnetic recording tape to extend from one reel to the other reel via an operative path substantially along the front wall section by way of guide rollers rotatably disposed at respective corner areas adjacent the front wall section.
The digital compact cassette 1 also comprises a protective slide shutter 1d mounted on the casing for movement between open and closed positions in a direction widthwise of the digital compact cassette 1 as shown in FIGS. 9(b) and 9(c), respectively, The protective shutter 1d is of a generally J-shaped cross-section having a base panel held flat against the bottom panel of the casing, a top panel held flat against the top panel of the casing and a shutter panel lying between the bottom and top panels. The shutter panel has first to third openings defined therein which are, when the shutter 1d is in the open position as shown in FIG. 9(c), aligned with the first to third access windows 5e to 5g to allow respective portions of the length of magnetic recording tape to be exposed to the outside of the casing.
Comparing the analog and digital compact cassettes 5 and 1, the both are similar in appearance. Specifically, the width L1 and the depth of the analog compact cassette 5 are equal to the width L3 and the depth of the digital compact cassette 1, respectively, however, the thickness D3 of the digital compact cassette 1 is somewhat greater than the minimum thickness D1 of the analog compact cassette 5.
Accordingly, in order for a cassette tape player to have a dual capability of accommodating either one of the analog compact cassette 5 and the digital compact cassette 1, a cassette holder used in the cassette tape player must be so designed as to accommodate the different thicknesses of the respective compact cassettes 5 and 1 and also as to accommodate the lateral guide bars 5h of the analog compact cassette 5.
In view of the foregoing, in the Japanese Laid-open Patent Publication No. 5-62311, published Mar. 12, 1993, (corresponding to U.S. patent application Ser. No. 07/936,592, filed Aug. 27, 1992, and EP Published Patent Application No. 530700-A2, published Mar. 10, 1993), the inventor of the present invention has previously suggested a cassette tape player employing a cassette holder of a type capable of satisfactorily and smoothly accommodating either one of the digital and analog compact cassettes.
It has however been found that, in the prior art cassette tape player of the kind referred to above, difficult has often been encountered in inserting either one of the digital and analog compact cassette. This is because, while the opening leading to a cassette receiving chamber defined in the cassette loading mechanism or the cassette holder is relatively narrow, some component parts of the cassette tape player such as, for example, a hingedly supported lid for selectively opening and closing the cassette chamber, which are positioned in the vicinity of the cassette loading mechanism, often provide an obstruction to the insertion of the tape cassette into the cassette receiving chamber.